The present invention relates an apparatus for assembling a motorcar vehicle body by welding right and left side panels to other vehicle body constituting members such as a floor panel, a roof panel, and the like.
There is conventionally known, in Japanese Published Unexamined Patent Application No. 212894/1983, an apparatus for assembling a motorcar vehicle body. In this apparatus, a welding apparatus and a presetting apparatus on its outer side are respectively provided on each side of an assembling station into which a floor panel and a roof panel are brought. A plurality of parts made up of an outer piece and various inner pieces, both constituting a side panel, are set to a presetting jig which is provided in the respective presetting apparatus. The above-described plurality of parts are received by a welding jig, which is respectively provided in the welding apparatus so as to be reversible between an inward-looking posture and an outward-looking posture, from the respective presetting jig while the welding jig is in the outward-looking posture. At the same time, these parts are welded together by welding guns which are respectively provided in the welding jig, to thereby assemble a side panel. Then, the respective welding jig is reversed to the inward-looking posture to thereby connect the side panel to the floor panel and the roof panel. Under this condition, the side panel is welded to the floor panel and the roof panel by other welding guns which are provided in the welding jig.
In addition, there is known another apparatus for assembling a motorcar vehicle body in Japanese Published Unexamined Patent Application No. 110581/1987. In this apparatus, positioning robots and welding robots are mounted on a respective stationary frame which is vertically provided on each side of an assembling station. Right and left side panels and other vehicle body constituting members such as a floor panel and the like are brought into the assembling station in a condition in which they are set in a predetermined positional relationship. These members are welded together by the welding robots while they are held in alignment by the positioning robots, to thereby assemble the motorcar vehicle body.
In the above-described former conventional art, it is necessary to change the welding jigs with the change in the type of the motorcar. Here, the welding jigs are expensive because many welding guns for assembling the side panels and those for assembling the motorcar vehicle body are mounted thereon. Therefore, there is a disadvantage in that the equipment cost becomes expensive because many of this kind of expensive welding jigs must be prepared for each type of motorcar.
In the above-described latter conventional art, on the other hand, it can easily cope with the change in the type of motorcar because it does not employ welding jigs. However, the side panels cannot be assembled on the welding jigs as is case with the above-described former conventional art. Therefore, it is necessary to provide additional assembling apparatuses for the side panels. It follows that the equipment cost becomes more expensive for this additional provision. Further, since the positioning of the vehicle body constituting members such as side panels, floor panel, and the like is performed by robots, there is a disadvantage in that the assembling accuracy is likely to become erroneous due to a change in positioning accuracy through repeated uses of the robots.